Product Overview

Construction details
Control spindle
The stainless steel control spindle has a double hydraulic seal (4)
consisting of two EPDM O-rings; this means that the upper part of
the unit can be replaced even when the system is operating.
Manual opening
With the electro-thermal actuator mounted, the valve is normally
closed. For manual opening, remove the electro-thermal actuator by
unscrewing the lower metal ring.
Installation
The 2-way valve, 676 series, can be installed in the supply or return
piping.
Operating principle
When a room thermostat operates, the thermo-electric actuator
causes the opening or closing of the valve actuator controlling the
system heat transfer fluid (or medium). The actuator operates via
a wax expansion thermostat heated up by a PTC resistor. When
the power supply is OFF, the device (actuator + valve) is “normally
closed” with the valve plug (1) pushed against the seat. When the
power supply is ON, the valve opens as the wax thermostatic element
expands (2) controlled directly by a PTC resistor (3). When the valve
plug reaches an average opening value of 80% the auxiliary micro-
switch contacts close, which can be used to start a circulator pump.
Code A B C D E Wt. (lb.)
676349A
1
/2" sweat union 3
11
⁄16" 2
3
⁄8" 3
1
/2"
3
⁄4" 1.25
676356A
3
⁄4" press 4
3
⁄4" 2
3
⁄8” 3
1
/2”
3
⁄4" 1.25
676359A
3
⁄4" sweat union 4
3
/16" 2
3
⁄8” 3
1
/2”
3
⁄4" 1.25
676369A 1” sweat union 5
3
/8" 2
3
⁄8” 3
1
/2”
3
⁄4" 1.25
Dimensions
B
A
D
E
C
B
A
D
E
C
Code A B C D E Wt. (lb.)
676249A
1
/2" sweat union 3
11
⁄16" 1
3
⁄4" 3
3
/4"
3
⁄4" 1.25
676256A
3
⁄4" press 4
3
⁄4" 1
3
⁄4” 3
3
/4”
3
⁄4" 1.25
676259A
3
⁄4" sweat union 4
3
/16" 1
3
⁄4” 3
3
/4”
3
⁄4" 1.25
676269A 1” sweat union 5
3
/8" 1
3
⁄4” 3
3
/4”
3
⁄4" 1.25
Metal Ring
1
4
3
2